Illumination unit, projection type display unit, and direct view type display unit

ABSTRACT

An illumination unit includes one or more light sources each including a solid-state light-emitting device having a light emission region configured of one or more light-emission spots, one or more traveling-direction angle conversion device each converting a traveling-direction-angle of light, and an integrator including a first fly-eye lens having cells which receive light from the traveling-direction angle conversion device and a second fly-eye lens having cells which receive light from the first fly-eye lens, the integrator uniformalizing illumination distribution in a predetermined illumination area. An optical system configured with the traveling-direction angle conversion device and the first and second fly-eye lenses has an optical magnification which allows each of light source images to have a size not exceeding a size of the cell in the second fly-eye lens, the light source images being formed on the second fly-eye lens by the respective cells in the first fly-eye lens.

CROSS REFERENCES TO RELATED APPLICATIONS

The present application claims priority to Japanese Priority PatentApplication JP 2010-229372 filed in the Japan Patent Office on Oct. 12,2010, the entire content of which is hereby incorporated by reference.

BACKGROUND

This application relates to an illumination unit using a solid-statelight-emitting device such as a light-emitting diode (LED), and aprojection type display unit and a direct view type display unitincluding the same.

In recent years, projectors projecting pictures onto a screen have beenwidely used in homes besides offices. The projector modulates light froma light source with use of a light valve to generate imaging light, andprojects the imaging light onto a screen, thereby performing display.Nowadays, palm-sized ultra-compact projectors, mobile phones with abuilt-in ultra-compact projector, and the like are being introduced.

SUMMARY

Incidentally, as a light source used in a projector, a discharge lampwith high luminance is standard. The discharge lamp, however, isrelatively large in size and consumes larger power. Therefore, as alight source alternative to the discharge lamp, solid-statelight-emitting devices such as a light-emitting diode (LED), a laserdiode (LD), and an organic EL (OLED) has been attracted attention (forexample, Japanese Unexamined Patent Application Publication No.2008-134324). These solid-state light-emitting devices are moreadvantageous than the discharge lamp in terms of high reliability inaddition to the smaller size and the lower consumed power.

In a case where the above-described solid-state light-emitting device isused as a light source of a projector, it is considered that other maincomponents included in the projector are also downsized to furtherdownsize the projector itself. However, when the other main componentsincluded in the projector are downsized, light use efficiency is likelyto be lowered. Therefore, for example, even if light amount of a lightsource is increased by increasing the number of the above-describedsolid-state light-emitting devices, there is a possibility to raise anissue that desired luminance is not obtained due to the lowering oflight use efficiency.

It is desirable to provide a small illumination unit with improved lightuse efficiency. In addition, it is desirable to provide a projectiontype display unit and a direct view type display unit using such a smallillumination unit.

An illumination unit according to an embodiment of the disclosureincludes one or more light sources each including a solid-statelight-emitting device having a light emission region configured of oneor more light-emission spots, one or more traveling-direction angleconversion device each converting a traveling-direction-angle of lightentering from the solid-state light-emitting device, and an integratorincluding a first fly-eye lens having cells which receive light from thetraveling-direction angle conversion device and a second fly-eye lenshaving cells which receive light from the first fly-eye lens. Theintegrator uniformalizes illumination distribution in a predeterminedillumination area which is to be illuminated by light from thetraveling-direction angle conversion device. An optical systemconfigured with the traveling-direction angle conversion device and thefirst and second fly-eye lenses has an optical magnification whichallows each of light source images to have a size not exceeding a sizeof the cell in the second fly-eye lens, the light source images beingformed on the second fly-eye lens by the respective cells in the firstfly-eye lens.

A projection type display unit according to an embodiment of thedisclosure includes: an illumination optical system; a spatialmodulation device modulating light from the illumination optical systembased on an input picture signal to generate imaging light; and aprojection optical system projecting the imaging light generated by thespatial modulation device. The illumination optical system included inthe projection type display unit has the same components as those in theabove-described illumination unit.

A direct view type display unit according to an embodiment of thedisclosure includes: an illumination optical system; a spatialmodulation device modulating light from the illumination optical systembased on an input picture signal to generate imaging light; a projectionoptical system projecting the imaging light generated by the spatialmodulation device; and a transmissive screen displaying the imaginglight projected from the projection optical system. The illuminationoptical system included in the direct view type display unit has thesame components as those in the above-described illumination unit.

In the illumination unit, the projection type display unit, and thedirect view type display unit according to the embodiment of thedisclosure, an optical magnification of an optical system configuredwith the traveling-direction angle conversion device and the first andsecond fly-eye lenses is set so that each light source image formed onthe second fly-eye lens by each cell of the first fly-eye lens has asize not exceeding a size of one cell of the second fly-eye lens.Therefore, light entering the second fly-eye lens efficiently reachesthe illumination area.

In the illumination unit, the projection type display unit, and thedirect view type display unit according to the embodiment of thedisclosure, in a case where the solid-state light-emitting device isconfigured of a single chip which emits light in a predeterminedwavelength range or is configured of a plurality of chips which emitlight in the same wavelength range or different wavelength ranges, theoptical magnification of the optical system configured with thetraveling-direction angle conversion device and the first and secondfly-eye lenses preferably satisfies the following expression:

h=P*m≦h _(FEL2)

where h is a size of the light source image,

P is a size of the light emission region (the size is equal to a size ofa light-emission spot of the chip when the solid-state light-emittingdevice is configured of one chip, and the size is equal to a size of anenclosure which encloses light-emission spots of all the chips with aminimum inner area when the solid-state light-emitting device isconfigured of a plurality of chips),

m is an optical magnification of an optical system configured with thetraveling-direction angle conversion device and the first and secondfly-eye lenses, and

h_(FEL2) is a size of the cell in the second fly-eye lens.

In the illumination unit, the projection type display unit, and thedirect view type display unit according to the embodiment of thedisclosure, in a case where the traveling-direction angle conversiondevice converts a traveling-direction angle of light entering from thesolid-state light-emitting device to be equal to or close to atraveling-direction angle of parallelized light, a focal length of thetraveling-direction angle conversion device and a focal length of eachof the first and the second fly-eye lenses preferably satisfy thefollowing expression. At this time, in a case where each cell of thefirst and second fly-eye lenses has an aspect ratio other than 1, thefocal length of the traveling-direction angle conversion device and thefocal length of each of the first and second fly-eye lenses arepreferably set with the aspect ratio taken into consideration.

h=P*(f _(FEL) /f _(CL))≦h _(FEL2)

where f_(FEL) is a focal length of each of the first and second fly-eyelenses, and

f_(CL) is a focal length of the traveling-direction angle conversiondevice.

In the illumination unit, the projection type display unit, and thedirect view type display unit according to the embodiment of thedisclosure, the traveling-direction angle conversion device has a focallength and a numerical aperture which allow light which enters theretoto have a beam size not exceeding a size of the traveling-directionangle conversion device. In this case, the focal length and thenumerical aperture of the traveling-direction angle conversion devicepreferably satisfy the following expression. At this time, in a casewhere the traveling-direction angle conversion device has an aspectratio other than 1, the focal length and the numerical aperture of thetraveling-direction angle conversion device are preferably set with theaspect ratio taken into consideration.

φ_(CL)=2*f _(CL) *NA≦h _(CL)

where φCL is a beam size of light entering the traveling-direction angleconversion device,

NA is the numerical aperture of the traveling-direction angle conversiondevice, and

h_(CL) is a size of the traveling-direction angle conversion device.

In the illumination unit, the projection type display unit, and thedirect view type display unit according to the embodiment of thedisclosure, in a case where a plurality of light sources and a pluralityof traveling-direction angle conversion devices are provided, each ofthe light sources may be formed in a manner of a package including thesolid-state light-emitting device therein, and each of thetraveling-direction angle conversion devices may be arranged for each ofthe packages. In this case, the illumination unit preferably furtherincludes a light path unifying device unifying light beams, which havepassed through the respective traveling-direction angle conversiondevices, into a single light path. In addition, in the illuminationunit, the projection type display unit, and the direct view type displayunit according to the embodiment of the disclosure, in a case where aplurality of light sources and one traveling-direction angle conversiondevice are provided, each of the light sources may be formed in a mannerof a package including the solid-state light-emitting device therein. Inthis case, the illumination unit preferably further includes a lightpath unifying device unifying light emitted from each solid-statelight-emitting device, into a single light path. Moreover, in theillumination unit, the projection type display unit, and the direct viewtype display unit according to the embodiment of the disclosure, in acase where one light source and one traveling-direction angle conversiondevice are provided, the light source may be formed in a manner of apackage including the solid-state light-emitting device therein.Furthermore, in the illumination unit, the projection type display unit,and the direct view type display unit according to the embodiment of thedisclosure, the chip may be configured with a light emitting diode, anorganic EL light-emitting device, or a laser diode. Moreover, in theillumination unit, the projection type display unit, and the direct viewtype display unit according to the embodiment of the disclosure, a ratioof a vertical magnification factor to a horizontal magnification factorof the traveling-direction angle conversion device may be equal to aninverse of the aspect ratio of each cell in the second fly-eye lenses.

According to the illumination unit, the projection type display unit,and the direct view type display unit of the disclosure, since one lightsource image is not formed over a plurality of cells, light useefficiency in the illumination unit may be improved.

In addition, in the illumination unit, the projection type display unit,and the direct view type display unit according to the embodiment of thedisclosure, in the case where each cell of the first and second fly-eyelenses has an aspect ratio other than 1, when the focal length of thetraveling-direction angle conversion device and the focal length of eachof the first and second fly-eye lenses are set with the aspect ratiotaken into consideration, light use efficiency in the illumination unitmay be further improved. Moreover, in the illumination unit, theprojection type display unit, and the direct view type display unitaccording to the embodiment of the disclosure, in a case where thetraveling-direction angle conversion device has an aspect ratio otherthan 1, when the focal length and the numerical aperture of thetraveling-direction angle conversion device are set with the aspectratio taken into consideration, light use efficiency in the illuminationunit may be further improved.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1A and 1B are diagrams illustrating a schematic configuration of aprojector according to a first embodiment of the disclosure.

FIGS. 2A and 2B are diagrams illustrating an example of light paths inthe projector in FIGS. 1A and 1B.

FIGS. 3A and 3B are diagrams illustrating an example of a top surfaceconfiguration and a cross-sectional configuration of a light source inFIGS. 1A and 1B.

FIGS. 4A and 4B are diagrams illustrating another example of the topsurface configuration and the cross-sectional configuration of the lightsource in FIGS. 1A and 1B.

FIGS. 5A and 5B are diagrams illustrating still another example of thetop surface configuration and the cross-sectional configuration of thelight source in FIGS. 1A and 1B.

FIGS. 6A to 6C are diagrams illustrating an example of a light-emissionspot of the light source in FIGS. 1A and 1B.

FIGS. 7A and 7B are diagrams illustrating schematic configurations offly-eye lenses in FIGS. 1A and 1B.

FIG. 8 is a schematic diagram for describing a size of an illuminationarea in FIGS. 1A and 1B.

FIG. 9 is a schematic diagram illustrating an example of light sourceimages appearing in a fly-eye lens disposed backward in the projector inFIGS. 1A and 1B.

FIGS. 10A and 10B are diagrams illustrating a schematic configuration ofa projector according to a second embodiment of the disclosure.

FIGS. 11A and 11B are diagrams illustrating an example of light paths inthe projector in FIGS. 10A and 10B.

FIGS. 12A and 12B are diagrams illustrating a schematic configuration ofa projector according to a third embodiment of the disclosure.

FIGS. 13A and 13B are diagrams illustrating an example of light paths inthe projector in FIGS. 12A and 12B.

FIGS. 14A and 14B are diagrams illustrating a schematic configuration ofa projector according to a fourth embodiment of the disclosure.

FIGS. 15A and 15B are diagrams illustrating an example of across-sectional configuration of a polarization splitter in FIGS. 14Aand 14B.

FIG. 16 is a diagram illustrating an example of a top surfaceconfiguration of a retardation plate array in FIGS. 14A and 14B.

FIGS. 17A to 17C are diagrams illustrating an example of light paths inthe projector in FIGS. 14A and 14B.

FIG. 18 is a schematic diagram illustrating an example of light sourceimages appearing in a fly-eye lens disposed backward in the projector inFIGS. 14A and 14B.

FIG. 19 is a table illustrating designed values in examples according tothe first to third embodiments.

FIG. 20 is a table illustrating designed values in example according tothe fourth embodiment.

FIG. 21A is a diagram illustrating an example of a cross-sectionalconfiguration of a modification of the light source according to each ofthe first to fourth embodiments, and FIG. 21B is a diagram illustratinga solid-state light-emitting device included in the light source of FIG.21A, viewed from a light emission surface side.

FIG. 22A is a diagram illustrating another example of thecross-sectional configuration of the light source of FIG. 21A, and FIG.22B is a diagram illustrating a solid-state light-emitting deviceincluded in the light source of FIG. 22A, viewed from a light emissionsurface side.

FIG. 23A is a diagram illustrating still another example of thecross-sectional configuration of the light source of FIG. 21A, and FIG.23B is a diagram illustrating a solid-state light-emitting deviceincluded in the light source of FIG. 23A, viewed from a light emissionsurface side.

FIG. 24A is a diagram illustrating an example of a cross-sectionalconfiguration of the light source of FIG. 21A, which is rotated by 90degrees in XY plane, and FIG. 24B is a diagram illustrating asolid-state light-emitting device included in the light source of FIG.24A, viewed from a light emission surface side.

FIG. 25A is a diagram illustrating an example of a cross-sectionalconfiguration of the light source of FIG. 22A, which is rotated by 90degrees in XY plane, and FIG. 25B is a diagram illustrating asolid-state light-emitting device included in the light source of FIG.25A, viewed from a light emission surface side.

FIG. 26A is a diagram illustrating an example of a cross-sectionalconfiguration of the light source of FIG. 23A, which is rotated by 90degrees in XY plane, and FIG. 26B is a diagram illustrating asolid-state light-emitting device included in the light source of FIG.26A, viewed from a light emission surface side.

FIG. 27 is a diagram illustrating a schematic configuration of arear-projection display device using an illumination optical systemaccording to any of the above-described embodiments.

DETAILED DESCRIPTION

Embodiments of the present application will be described below in detailwith reference to the drawings.

1. First embodiment (FIGS. 1A and 1B to FIG. 9)

Example of unifying light beams from each light source into a singlelight path after parallelization of light with use of coupling lenses

2. Second embodiment (FIGS. 10A and 10B and FIGS. 11A and 11B)

Example of unifying light beams from each light source into a singlelight path before parallelization of light with use of coupling lenses

3. Third embodiment (FIGS. 12A and 12B and FIGS. 13A and 13B)

Example of emitting light of different wavelength ranges from a singlepackage to eliminate unification of light paths

4. Fourth embodiment (FIGS. 14A and 14B to FIG. 18)

Example in which a polarization splitter and a retardation plate arrayare provided

5. Examples (FIG. 19 and FIG. 20)

6. Modifications (FIGS. 21A and 21B to FIG. 27)

First Embodiment

Configuration

FIGS. 1A and 1B are diagrams illustrating a schematic configuration of aprojector 1 according to a first embodiment of the disclosure. Note thatthe projector 1 corresponds to a specific example of “a projection typedisplay unit” in the disclosure. FIG. 1A illustrates a configurationexample of the projector 1 viewed from above (from y-axis direction),and FIG. 1B illustrates a configuration example of the projector 1viewed from the side (from x-axis direction). FIGS. 2A and 2B arediagrams illustrating an example of light paths in the projector 1 ofFIGS. 1A and 1B. FIG. 2A illustrates an example of light paths in theprojector 1 viewed from above (from y-axis direction) and FIG. 2Billustrates an example of light paths in the projector 1 viewed from theside (from x-axis direction).

Typically, y-axis corresponds to a vertical direction, and x-axiscorresponds to a horizontal direction, however, y-axis may correspond toa horizontal direction and x-axis may correspond to a verticaldirection. Note that in the following description, for convenience, thedescription will be given on the assumption that the y-axis correspondsto a vertical direction and x-axis corresponds to a horizontaldirection. In addition, in the following description, it is assumed that“lateral direction” indicates x-axis direction and “longitudinaldirection” indicates y-axis direction.

The projector 1 includes, for example, an illumination optical system1A, a spatial modulation device 60, and a projection optical system 70.The spatial modulation device 60 modulates light from the illuminationoptical system 1A based on an input picture signal to generate imaginglight. The projection optical system 70 projects the imaging lightgenerated by the spatial modulation device 60 onto a reflective screen2. Note that the illumination optical system 1A corresponds to aspecific example of “an illumination unit”.

The illumination optical system 1A supplies light flux illuminating anillumination area 60A (surface to be illuminated) of the spatialmodulation device 60. Note that, if necessary, any optical device may beprovided in a region through which light of the illumination opticalsystem 1A passes. For example, in a region though which light of theillumination optical system 1A passes, a filter or the like for dimminglight other than visible light of the light from the illuminationoptical system 1A may be provided.

As illustrated in FIGS. 1A and 1B, for example, the illumination opticalsystem 1A includes light sources 10A, 10B, and 10C, coupling lenses(traveling-direction angle conversion devices) 20A, 20B, and 20C, alight path unifying device 30, an integrator 40, and a condenser lens50. The light path unifying device 30 unifies light beams from the lightsources 10A, 10B and 10C, into a single light path, and is configuredof, for example, two dichroic mirrors 30A and 30B. The integrator 40equalizes illumination distribution of light in the illumination area60A, and is configured of, for example, a pair of fly-eye lenses 40A and40B. On an optical axis of the light source 10A, the coupling lens 20A,the light path unifying device 30, the integrator 40, and the condenserlens 50 are arranged in this order from the light source 10A side. Anoptical axis of the light source 10B is orthogonal to the optical axisof the light source 10A in the dichroic mirror 30A, and on the opticalaxis of the light source 10B, the coupling lens 20B and the dichroicmirror 30A are arranged in this order from the light source 10B side. Anoptical axis of the light source 10C is orthogonal to the optical axisof the light source 10A in the dichroic mirror 30B, and on the opticalaxis of the light source 10C, the coupling lens 20C and the dichroicmirror 30B are arranged in this order from the light source 10C side.

Note that in FIGS. 1A and 1B, although exemplified is a case where eachcomponents of the projector 1 (except for the light sources 10B and 10C,and the coupling lenses 20B and 20C) are arranged on a line parallel toz-axis, some components of the projector 1 may be arranged on a line notparallel to z-axis. For example, although not illustrated, theillumination optical system 1A may be arranged so that the optical axisof the illumination optical system 1A is along a direction orthogonal toz-axis by rotating the whole illumination optical system 1A by 90degrees from a state of FIGS. 1A and 1B. However, in this case, anoptical device (for example, a mirror) which directs light output fromthe illumination optical system 1A to the spatial modulation device 60needs to be provided. Moreover, for example, the light source 10A, thecoupling lens 20A, and the light path unifying device 30 may be arrangedso that the optical axes of these components are along a directionorthogonal to z-axis by rotating these components by 90 degrees from thestate of FIGS. 1A and 1B. However, also in this case, an optical device(for example, a mirror) which directs light output from the light pathunifying device 30 to the integrator 40 needs to be provided.

As illustrated in FIGS. 3A and 3B to FIGS. 5A and 5B, for example, thelight sources 10A, 10B, and 10C each have a solid-state light-emittingdevice 11 and a package 12 supporting and covering the solid-statelight-emitting device 11. The solid-state light-emitting device 11 emitslight from a light emission region which is configured of one or moredot-like light-emission spots, or one or more non-dot-likelight-emission spots. The solid-state light-emitting device 11 may beconfigured of a single chip 11A emitting light of a predeterminedwavelength range, for example, as illustrated in FIGS. 3A and 3B, or maybe configured of a plurality of chips 11A emitting light of the samewavelength range or with different wavelength ranges, for example, asillustrated in FIGS. 4A and 4B and FIGS. 5A and 5B. In a case where thesolid-state light-emitting device 11 is configured of a plurality ofchips 11A, the chips 11A are arranged in a lateral line, for example, asillustrated in FIGS. 4A and 4B, or are arranged in lateral andlongitudinal directions, that is, in a lattice, for example, asillustrated in FIGS. 5A and 5B. The number of the chips 11A included inthe solid-state light-emitting device 11 may be different for each ofthe light sources 10A, 10B, and 10C, or may be the same for all of thelight sources 10A, 10B, and 10C.

In a case where the solid-state light-emitting device 11 is configuredof a single chip 11A, the size (W_(V)*W_(H)) of the solid-statelight-emitting device 11 is equal to the size (W_(V1)*W_(H1)) of thesingle chip 11A, for example, as illustrated in FIG. 3A. On the otherhand, in a case where the solid-state light-emitting device 11 isconfigured of a plurality of chips 11A, when all chips 11A are regardedas one group, the size of the solid-state light-emitting device 11 isequal to the size of the group, for example, as illustrated in FIG. 4Aand FIG. 5A. In a case where the plurality of chips 11A are arranged ina lateral line, the size (W_(V)*W_(H)) of the solid-state light-emittingdevice 11 is W_(V1)*2W_(H1) in the example of FIG. 4A. Moreover, in acase where the plurality of chips 11A are arranged in the lateral andlongitudinal directions, that is, in a lattice, the size (W_(V)*W_(H))of the solid-state light-emitting device 11 is 2W_(V1)*2W_(H1) in theexample of FIG. 5A.

The chip 11A is configured with a light-emitting diode (LED), an organicEL light-emitting device (OLED), or a laser diode (LD). All chips 11Aincluded in each of the light sources 10A, 10B, and 10C may beconfigured with LED, OLED, or LD. In addition, chips 11A included in oneor more of the light sources 10A, 10B, and 10C may be configured withLED, and chips 11A included in the other light source(s) may beconfigured with OLED. Moreover, chips 11A included in one or more of thelight sources 10A, 10B, and 10C may be configured with LED, and chips11A included in the other light source(s) may be configured with LD.Furthermore, chips 11A included in one or more of the light sources 10A,10B, and 10C may be configured with OLED, and chips 11A included in theother light source(s) may be configured with LD.

The chips 11A included in each of the light sources 10A, 10B, and 10Ceach emit light of a wavelength range different for each of the lightsources 10A, 10B, and 10C, for example. The chips 11A included in thelight source 10A emit, for example, light with wavelength ofapproximately 400 nm to 500 nm (blue light). The chips 11A included inthe light source 10B emit, for example, light with wavelength ofapproximately 500 nm to 600 nm (green light). The chips 11A included inthe light source 10C emit, for example, light with wavelength ofapproximately 600 nm to 700 nm (red light). Incidentally, the chips 11Aincluded in the light source 10A may emit light other than blue light(green light or red light). In addition, the chips 11A included in thelight source 10B may emit light other than green light (blue light orred light). Moreover, the chips 11A included in the light source 10C mayemit light other than red light (green light or blue light).

As illustrated in FIGS. 3A and 3B to FIGS. 6A to 6C, for example, thechip 11A has a light-emission spot 11B with a size (P_(V1)*P_(H1))smaller than the size (W_(V1)*W_(H1)) of the chip 11A. Thelight-emission spot 11B corresponds to a region (light emission region)from which the chip 11A emits light when a current is injected into thechip 11A to drive the chip 11A. In a case where the chip 11A isconfigured of LED or OLED, the light-emission spot 11B has anon-dot-like shape (a planar shape), and in a case where the chip 11A isconfigured of LD, the light-emission spot 11B has a dot-like shapesmaller than the light-emission spot 11B in the case of LED or OLED.

In the case where the solid-state light-emitting device 11 is configuredof a single chip 11A, the number of the light-emission spots 11B is, forexample, one as illustrated in FIG. 6A. On the other hand, in the casewhere the solid-state light-emitting device 11 is configured of aplurality of chips 11A, the number of the light-emission spots 11B isequal to the number of the chips 11A, for example, as illustrated inFIGS. 6B and 6C. Herein, in the case where the solid-statelight-emitting device 11 is configured of a single chip 11A, the size(P_(V)*P_(H)) of the light emission region of the solid-statelight-emitting device 11 is equal to the size (P_(V1)*P_(H1)) of thelight-emission spot 11B. On the other hand, in the case where thesolid-state light-emitting device 11 is configured of a plurality ofchips 11A, the size (P_(V)*P_(H)) of the light emission region as thesolid-state light-emitting device 11 is equal to a size of an enclosurewhich encloses the light-emission spots 11B of all chips 11A with aminimum inner area. In the case where the plurality of chips 11A arearranged in a lateral line, the size (P_(V)*P_(H)) of the light emissionregion is larger than P_(V1)*2P_(H1) but smaller than W_(V)*W_(H) in theexample of FIG. 6B. In addition, in the case where the plurality ofchips 11A are arranged in lateral and longitudinal directions, i.e., ina lattice, the size (P_(V)*P_(H)) of the light emission region is largerthan 2P_(V1)*2P_(H1) but smaller than W_(V)*W_(H) in the example of FIG.6C.

As illustrated in FIGS. 2A and 2B, for example, the coupling lens 20Asubstantially parallelizes light emitted from the light source 10A, andconverts a traveling-direction angle (θ_(H), θ_(V)) of the light emittedfrom the light source 10A to be equal to or close to atraveling-direction angle of parallelized light. The coupling lens 20Ais disposed on a position where light within the traveling-directionangle contained in the light emitted from the light source 10A entersthe coupling lens 20A. As illustrated in FIGS. 2A and 2B, for example,the coupling lens 20B substantially parallelizes light emitted from thelight source 10B, and converts a traveling-direction angle (θ_(H),θ_(V)) of the light emitted from the light source 10B to be equal to orclose to a traveling-direction angle of parallelized light. The couplinglens 20B is disposed on a position allowing light within thetraveling-direction angle of light emitted from the light source 10B toenter the coupling lens 20B. As illustrated in FIGS. 2A and 2B, forexample, the coupling lens 20C substantially parallelizes light emittedfrom the light source 10C, and converts a traveling-direction angle(θ_(H), θ_(V)) of the light emitted from the light source 10C to beequal to or close to a traveling-direction angle of parallelized light.The coupling lens 20C is disposed on a position allowing light withinthe traveling-direction angle of light emitted from the light source 10Cto enter the coupling lens 20C. In other words, the coupling lenses 20A,20B, and 20C are arranged one to one for the light sources 10A, 10B, and10C (for each package). Note that each of the coupling lenses 20A, 20B,and 20C may be configured of one or more lenses.

The dichroic mirrors 30A and 30B each include a mirror with wavelengthselectivity. Incidentally, for example, the above-described mirror isconfigured by depositing a multilayer interference film. As illustratedin FIGS. 2A and 2B, for example, the dichroic mirror 30A allows lightentering from the back side of the mirror (light entering from the lightsource 10A side) to pass therethrough to the front side of the mirror,and reflects light entering from the front side of the mirror (lightentering from the light source 10B side) by the mirror. On the otherhand, the dichroic mirror 30B allows light entering from the back sideof the mirror (light of the light sources 10A and 10B entering from thedichroic mirror 30A side) to pass therethrough to the front side of themirror, and reflects light entering from the front side of the mirror(light entering from the light source 10C side) by the mirror asillustrated in FIGS. 2A, and 2B, for example. Therefore, the light pathunifying device 30 unifies individual light fluxes emitted from thelight sources 10A, 10B, and 10C to generate a single light flux.

Each of the fly-eye lenses 40A and 40B is configured of a plurality oflenses (cells) arranged in a predetermined arrangement pattern (in thiscase, in a matrix of vertical*horizontal=4*3). Each of the cells 42included in the fly-eye lens 40B is arranged to face each cell 41 of thefly-eye lens 40A. The fly-eye lens 40A is disposed on a focal position(or substantially on a focal position) of the fly-eye lens 40B, and thefly-eye lens 40B is disposed on a focal position (or substantially on afocal position) of the fly-eye lens 40A. Accordingly, in the integrator40, light fluxes divided by the fly-eye lens 40A is each focusedsubstantially on a lens surface of the image side of the fly-eye lens40B, thereby forming secondary light source planes (light source images)on the focal point. The secondary light source planes are located onpositions of a plane conjugate to an entrance pupil of the projectionoptical system 70. The secondary light source planes are, however, notnecessarily located strictly on the positions of a plane conjugate to anentrance pupil of the projection optical system 70, and may be locatedwithin an acceptable region in design. The fly-eye lenses 40A and 40Bmay be integrally formed.

Light fluxes emitted from the light sources 10A, 10B, and 10C generallyshow non-uniform intensity distribution on a plane perpendicular to thetraveling direction of light fluxes. Therefore, if the light fluxes aredirected as it is to the illumination area 60A (surface to beilluminated), illumination distribution in the illumination area 60A isnon-uniform. However, as described above, when the light fluxes emittedfrom the light sources 10A, 10B, and 10C are divided into a plurality oflight fluxes by the integrator 40 and then guided to the illuminationarea 60A in a superimposed manner, the illumination distribution in theillumination area 60A is allowed to be uniform.

The condenser lens 50 collects light fluxes from multiple light sourcesformed by the integrator 40 to illuminate the illumination area 60A in asuperimposed manner. The spatial modulation device 60 modulates lightfluxes from the illumination optical system 1A two-dimensionally, basedon a color image signal corresponding to wavelength component of each ofthe light sources 10A, 10B, and 10C, and thus generates imaging light.As illustrated in FIGS. 2A and 2B, for example, the spatial modulationdevice 60 is a transmissive device, and is configured of, for example, atransmissive liquid crystal panel. Incidentally, although notillustrated, the spatial modulation device 60 may be configured of areflective device such as a reflective liquid crystal panel and adigital micro mirror device. However, in such a case, light reflected bythe spatial modulation device 60 needs to enter the projection opticalsystem 70.

Next, features of the projector 1 will be described.

Feature 1

In the embodiment, the focal length of each of the coupling lenses 20A,20B, and 20C, and the focal length of each of the fly-eye lenses 40A and40B are set so that each light source image S formed on the fly-eye lens40B by each cell 41 of the fly-eye lens 40A has a size not exceeding thesize of one cell 42 of the fly-eye lens 40B. Following expressionsrepresent the relationship. In addition, the relationship isschematically illustrated in FIG. 9. In FIG. 9, a case where each cellof the fly-eye lenses 40A and 40B has an aspect ratio other than 1 isillustrated. Incidentally, FIG. 9 will be described in detail later.

h ₁ =P ₁*(f _(FEL) /f _(CL1))≦h _(FEL2)  (1)

h ₂ =P ₂*(f _(FEL) /f _(CL2))≦h _(FEL2)  (2)

h ₃ =P3*(fFEL/fCL3)≦hFEL2  (3)

where h₁ is a size of the light source image S (a light source image S₁)formed by light of the light source 10A,

h₂ is a size of the light source image S (a light source image S₂)formed by light of the light source 10B,

h₃ is a size of the light source image S (a light source image S₃)formed by light of the light source 10C,

P₁ is a size of a light emission region of the solid-statelight-emitting device 11 included in the light source 10A,

P₂ is a size of a light emission region of the solid-statelight-emitting device 11 included in the light source 10B,

P₃ is a size of a light emission region of the solid-statelight-emitting device 11 included in the light source 10C,

f_(FEL) is a focal length of each of the fly-eye lenses 40A and 40B,

-   -   f_(CL1) is a focal length of the coupling lens 20A,    -   f_(CL2) is a focal length of the coupling lens 20B,    -   f_(CL3) is a focal length of the coupling lens 20C, and    -   h_(FEL2) is a size of one cell 42 of the fly-eye lens 40B.

Note that in the case where the solid-state light-emitting device 11included in the light source 10A is configured of a single chip 11A, P₁is equal to a size of the light-emission spot 11B of the chip 11A.Likewise, in the case where the solid-state light-emitting device 11included in the light source 10B is configured of a single chip 11A, P₂is equal to a size of the light-emission spot 11B of the chip 11A, andin the case where the solid-state light-emitting device 11 included inthe light source 10C is configured of a single chip 11A, P₃ is equal toa size of the light-emission spot 11B of the chip 11A. In the case wherethe solid-state light-emitting device 11 included in the light source10A is configured of a plurality of chips 11A, P₁ is equal to a size ofan enclosure which encloses the light-emission spots 11B of all chips11A with a minimum inner area. Likewise, in the case where thesolid-state light-emitting device 11 included in the light source 10B isconfigured of a plurality of chips 11A, P₂ is equal to a size of anenclosure which encloses the light-emission spots 11B of all chips 11Awith a minimum inner area. In the case where the solid-statelight-emitting device 11 included in the light source 10C is configuredof a plurality of chips 11A, P₃ is equal to a size of an enclosure whichencloses the light-emission spots 11B of all chips 11A with a minimuminner area. In addition, in a case where the coupling lens 20A isconfigured of a plurality of lenses, f_(CL1) is a combined focal lengthof the lenses. Likewise, in a case where the coupling lens 20B isconfigured of a plurality of lenses, f_(CL2) is a combined focal lengthof the lenses. In a case where the coupling lens 20C is configured of aplurality of lenses, f_(CL3) is a combined focal length of the lenses.

As expressions substantially equivalent to the above-describedexpressions (1) to (3), the following expressions (4) to (6) are cited.The expressions (4) to (6) are especially advantageous in the case wherethe size of the light emission region of the solid-state light-emittingdevice 11 is substantially equal to the size of the solid-statelight-emitting device 11.

h ₁ =W ₁*(f _(FEL) /f _(CL1))≦h _(FEL2)  (4)

h ₂ =W ₂*(f _(FEL) /f _(CL2))≦h _(FEL2)  (5)

h ₃ =W ₃*(f _(FEL) /f _(CL3))≦h _(FEL2)  (6)

where W₁ is a size of the solid-state light-emitting device 11 includedin the light source 10A,

W₂ is a size of the solid-state light-emitting device 11 included in thelight source 10B, and

W₃ is a size of the solid-state light-emitting device 11 included in thelight source 10C.

Note that in the case where the solid-state light-emitting device 11 isconfigured of a single chip 11A, W is equal to the size of the chip 11A.In addition, in a case where the solid-state light-emitting device 11 isconfigured of a plurality of chips 11A which are regarded as a singlechip, W is equal to the size of the single chip.

Incidentally, in the embodiment, for example, as illustrated in FIGS. 7Aand 7B, in a case where each of the cells 41 and 42 of the fly-eyelenses 40A and 40B has an aspect ratio other than 1, it is preferablethat the focal length of each of the coupling lenses 20A, 20B, and 20Cand the focal length of each of the fly-eye lenses 40A and 40B satisfythe following six relational expressions. Moreover, it is preferablethat the ratio of horizontal focal length to vertical focal length ofeach of the coupling lenses 20A, 20B, and 20C (f_(CL1H)/f_(CL1V),f_(CL2H)/f_(CL2V), and f_(CL3H)/f_(CL3V)) (anamorphic ratio) be equal tothe inverse (h_(FEL2V)/h_(FEL2H)) of the aspect ratio of the size ofeach cell 42 of the fly-eye lens 40B, and the illumination opticalsystem 1A be an anamorphic optical system. For example, when each cell42 of the fly-eye lens 40B is long in a first direction (for example, ina lateral direction), as the coupling lenses 20A, 20B, and 20C, thelenses whose focal lengths f_(CL1V), f_(CL2V), and f_(CL3V) are longerthan the focal lengths f_(CL1H), f_(CL2H), and f_(CL3H), respectively,are used. FIG. 9 schematically illustrates the following expressions (7)to (12).

h _(1H) =P _(1H)*(f _(FELH) /f _(CL1H))≦h _(FEL2H)  (7)

h _(2H) =P _(2H)*(f _(FELH) /f _(CL2H))≦h _(FEL2H)  (8)

h _(3H) =P _(3H)*(f _(FELH) /f _(CL3H))≦h _(FEL2H)  (9)

h _(1V) =P _(1V)*(f _(FELV) /f _(CL1V))≦h _(FEL2V)  (10)

h _(2V) =P _(2V)*(f _(FELV) /f _(CL2V))≦h _(FEL2V)  (11)

h _(3V) =P _(3V)*(f _(FELV) /f _(CL3V))≦h _(FEL2V)  (12)

where h_(1H) is a size in a first direction (for example, in a lateraldirection) of the light source image S (the light source image S₁)formed by light of the light source 10A,

h_(2H) is a size in the first direction (for example, in the lateraldirection) of the light source image S (the light source image S₂)formed by light of the light source 10B,

h_(3H) is a size in the first direction (for example, in the lateraldirection) of the light source image S (the light source image S₃)formed by light of the light source 10C,

h_(1V) is a size in a second direction orthogonal to the first direction(for example, in a longitudinal direction), of the light source image S(the light source image S₁) formed by light of the light source 10A,

h_(2V) is a size in the second direction orthogonal to the firstdirection (for example, in the longitudinal direction), of the lightsource image S (the light source image S₂) formed by light of the lightsource 10B,

h_(3V) is a size in the second direction orthogonal to the firstdirection (for example, in the longitudinal direction), of the lightsource image S (the light source image S₃) formed by light of the lightsource 10C,

P_(1H) is a size in the first direction or a direction correspondingthereto, of the light emission region of the solid-state light-emittingdevice 11 included in the light source 10A,

P_(2H) is a size in the first direction or a direction correspondingthereto, of the light emission region of the solid-state light-emittingdevice 11 included in the light source 10B,

P_(3H) is a size in the first direction or a direction correspondingthereto, of the light emission region of the solid-state light-emittingdevice 11 included in the light source 10C,

P_(1V) is a size in the second direction or a direction correspondingthereto, of the light emission region of the solid-state light-emittingdevice 11 included in the light source 10A,

P_(2V) is a size in the second direction or a direction correspondingthereto, of the light emission region of the solid-state light-emittingdevice 11 included in the light source 10B,

P_(3V) is a size in the second direction or a direction correspondingthereto, of the light emission region of the solid-state light-emittingdevice 11 included in the light source 10C,

f_(FELH) is a focal length in the first direction of each of the fly-eyelenses 40A and 40B,

f_(FELV) is a focal length in the second direction of each of thefly-eye lenses 40A and 40B,

f_(CL1H) is a focal length in the first direction or a directioncorresponding thereto, of the coupling lens 20A,

f_(CL2H) is a focal length in the first direction or a directioncorresponding thereto, of the coupling lens 20B,

f_(CL3H) is a focal length in the first direction or a directioncorresponding thereto, of the coupling lens 20C,

f_(CL1V) is a focal length in the second direction or a directioncorresponding thereto, of the coupling lens 20A,

f_(CL2V) is a focal length in the second direction or a directioncorresponding thereto, of the coupling lens 20B,

f_(CL3V) is a focal length in the second direction or a directioncorresponding thereto, of the coupling lens 20C,

h_(FEL2H) is a size in the first direction of one cell 42 of the fly-eyelens 40B, and

h_(FEL2V) is a size in the second direction of one cell 42 of thefly-eye lens 40B.

Herein, “a first direction or a direction corresponding thereto”indicates the first direction in a case where the light sources 10A,10B, and 10C and the coupling lenses 20A, 20B, and 20C are arranged onan optical axis of the integrator 40. In addition, “a first direction ora direction corresponding thereto” indicates the direction correspondingto the first direction because of layout of optical devices arranged ona light path from the light sources 10A, 10B, and 10C to the integrator40, in a case where the light sources 10A, 10B, and 10C and the couplinglenses 20A, 20B, and 20C are arranged on a light path away from theoptical axis of the integrator 40.

Moreover, “a second direction or a direction corresponding thereto”indicates the second direction in a case where the light sources 10A,10B, and 10C and the coupling lenses 20A, 20B, and 20C are arranged onthe optical axis of the integrator 40. Furthermore, “a second directionor a direction corresponding thereto” indicates the directioncorresponding to the second direction because of the layout of theoptical devices arranged on the light path from the light sources 10A,10B, and 10C to the integrator 40, in the case where the light sources10A, 10B, and 10C and the coupling lenses 20A, 20B, and 20C are arrangedon a light path away from the optical axis of the integrator 40.

Note that in the case where the solid-state light-emitting device 11included in the light source 10A is configured of a single chip 11A,P_(1H) is equal to a size in the first direction or a directioncorresponding thereto, of the light-emission spot 11B of the chip 11A.Likewise, in the case where the solid-state light-emitting device 11included in the light source 10B is configured of a single chip 11A,P_(2H) is equal to a size in the first direction or a directioncorresponding thereto, of the light-emission spot 11B of the chip 11A.In the case where the solid-state light-emitting device 11 included inthe light source 10C is configured of a single chip 11A, P_(3H) is equalto a size in the first direction or a direction corresponding thereto,of the light-emission spot 11B of the chip 11A. In addition, in the casewhere the solid-state light-emitting device 11 included in the lightsource 10A is configured of a plurality of chips 11A, P_(1H) is equal toa size in the first direction or a direction corresponding thereto, ofan enclosure which encloses the light-emission spots 11B of all chips11A with a minimum inner area. Likewise, in the case where thesolid-state light-emitting device 11 included in the light source 10B isconfigured of a plurality of chips 11A, P_(2H) is equal to a size in thefirst direction or a direction corresponding thereto, of an enclosurewhich encloses the light-emission spots 11B of all chips 11A with aminimum inner area. In the case where the solid-state light-emittingdevice 11 included in the light source 10C is configured of a pluralityof chips 11A, P_(3H) is equal to a size in a first direction or adirection corresponding thereto, of an enclosure which encloses thelight-emission spots 11B of all chips 11A with a minimum inner area. Onthe other hand, in the case where the solid-state light-emitting device11 included in the light source 10A is configured of a single chip 11A,P_(1V) is equal to a size in the second direction or a directioncorresponding thereto, of the light-emission spot 11B of the chip 11A.Likewise, in the case where the solid-state light-emitting device 11included in the light source 10B is configured of a single chip 11A,P_(2V) is equal to a size in the second direction or a directioncorresponding thereto, of the light-emission spot 11B of the chip 11A.In the case where the solid-state light-emitting device 11 included inthe light source 10C is configured of a single chip 11A, P_(3V) is equalto a size in the second direction or a direction corresponding thereto,of the light-emission spot 11B of the chip 11A. Moreover, in the casewhere the solid-state light-emitting device 11 included in the lightsource 10A is configured of a plurality of chips 11A, P_(1V) is equal toa size in the second direction or a direction corresponding thereto, ofan enclosure which encloses the light-emission spots 11B of all chips11A with a minimum inner area. Likewise, in the case where thesolid-state light-emitting device 11 included in the light source 10B isconfigured of a plurality of chips 11A, P_(2V) is equal to a size in thesecond direction or a direction corresponding thereto, of an enclosurewhich encloses the light-emission spots 11B of all chips 11A with aminimum inner area. In the case where the solid-state light-emittingdevice 11 included in the light source 10C is configured of a pluralityof chips 11A, P_(3V) is equal to a size in the second direction or adirection corresponding thereto, of an enclosure which encloses thelight-emission spots 11B of all chips 11A with a minimum inner area.

Moreover, in the embodiment, when each of the cells 41 and 42 of thefly-eye lenses 40A and 40B has an aspect ratio other than 1, it ispreferable that an aspect ratio of a size of each cell 41 of the fly-eyelens 40A and an aspect ratio of the illumination area 60A satisfy thefollowing relational expression. In this case, the aspect ratio H/V ofthe illumination area 60A has a correlation with resolution of thespatial modulation device 60, and for example, when the resolution ofthe spatial modulation device 60 is VGA (640*480), the aspect ratio H/Vis 640/480, and for example, when the resolution of the spatialmodulation device 60 is WVGA (800*480), the aspect ratio H/V is 800/480.

h _(FEL1H) /h _(FEL1V) =H/V  (13)

where h_(FEL1H) is a size in the first direction of one cell of thefly-eye lens 40A,

h_(FEL1V) is a size in the second direction of one cell of the fly-eyelens 40A,

H is a size in the first direction of the illumination area 60A, and

V is a size in the second direction of the illumination area 60A.

(Feature 2)

Moreover, in the embodiment, the focal length and the numerical apertureof each of the coupling lenses 20A, 20B, and 20C are set so that lightentering the coupling lenses 20A, 20B, and 20C has a beam size notexceeding the size of the coupling lenses 20A, 20B, and 20C,respectively. The relationship is expressed by the followingexpressions.

φ_(CL1)=2*f _(CL1) *NA ₁ ≦h _(CL1)  (14)

φ_(CL2)=2*f _(CL2) *NA ₂ ≦h _(CL2)  (15)

φ_(CL3)=2*f _(CL3) *NA ₃ ≦h _(CL3)  (16)

where φ_(CL1) is a beam size of light entering the coupling lens 20A,

φ_(CL2) is a beam size of light entering the coupling lens 20B,

φ_(CL3) is a beam size of light entering the coupling lens 20C, NA₁ isthe numerical aperture of the coupling lens 20A,

NA₂ is the numerical aperture of the coupling lens 20B,

NA₃ is the numerical aperture of the coupling lens 20C,

h_(CL1) is a size of the coupling lens 20A,

h_(CL2) is a size of the coupling lens 20B, and

h_(CL3) is a size of the coupling lens 20C.

Incidentally, in the embodiment, when the coupling lenses 20A, 20B, and20C each have an aspect ratio other than 1, it is preferable that thefocal length and the numerical aperture of each of the coupling lenses20A, 20B, and 20C satisfy the following two relational expressions.

φ_(CL1H)=2*f _(CL1H) *NA _(1H) ≦h _(CL1H)  (17)

φ_(CL2H)=2*f _(CL2H) *NA _(2H) ≦h _(CL2H)  (18)

φ_(CL3H)=2*f _(CL3H) *NA _(3H) ≦h _(CL3H)  (19)

φ_(CL1V)=2*f _(CL1V) *NA _(1V) ≦h _(CL1V)  (20)

φ_(CL2V)=2*f _(CL2V) *NA _(2V) ≦h _(CL2V)  (21)

φ_(CL3V)=2*f _(CL3V) *NA _(3V) ≦h _(CL3V)  (22)

where φ_(CL1H) is a beam size in the first direction (for Example, inthe lateral direction) or a direction corresponding thereto, of lightentering the coupling lens 20A,

φ_(CL2H) is a beam size in the first direction (for example, in thelateral direction) or a direction corresponding thereto, of lightentering the coupling lens 20B,

φ_(CL3H) is a beam size in the first direction (for example, in thelateral direction) or a direction corresponding thereto, of lightentering the coupling lens 20C,

φ_(CL1V) is a beam size in the second direction (for example, in thelongitudinal direction) or a direction corresponding thereto, of lightentering the coupling lens 20A,

φ_(CL2V) is a beam size in the second direction (for example, in thelongitudinal direction) or a direction corresponding thereto, of lightentering the coupling lens 20B,

φ_(CL3V) is a beam size in the second direction (for example, in thelongitudinal direction) or a direction corresponding thereto, of lightentering the coupling lens 20C,

NA_(1H) is the numerical aperture in the first direction or a directioncorresponding thereto, of the coupling lens 20A,

NA_(2H) is the numerical aperture in the first direction or a directioncorresponding thereto, of the coupling lens 20B,

NA_(3H) is the numerical aperture in the first direction or a directioncorresponding thereto, of the coupling lens 20C,

NA_(1V) is the numerical aperture in the second direction or a directioncorresponding thereto, of the coupling lens 20A,

NA_(2V) is the numerical aperture in the second direction or a directioncorresponding thereto, of the coupling lens 20B,

NA_(3V) is the numerical aperture in the second direction or a directioncorresponding thereto, of the coupling lens 20C,

h_(CL1H) is a size in the first direction or a direction correspondingthereto, of the coupling lens 20A,

h_(CL2H) is a size in the first direction or a direction correspondingthereto, of the coupling lens 20B,

h_(CL3H) is a size in the first direction or a direction correspondingthereto, of the coupling lens 20C,

h_(CL1V) is a size in the second direction or a direction correspondingthereto, of the coupling lens 20A,

h_(CL2V) is a size in the second direction or a direction correspondingthereto, of the coupling lens 20B, and

h_(CL3V) is a size in the second direction or a direction correspondingthereto, of the coupling lens 20C.

Functions and Effects

Subsequently, functions and effects of the projector 1 will bedescribed. In the embodiment, the focal lengths f_(CL1), f_(CL2), andf_(CL3) of the coupling lenses 20A, 20B, and 20C and the focal lengthf_(FEL) of each of the fly-eye lenses 40A and 40B are set so that eachlight source image S formed on the fly-eye lens 40B by each cell 41 ofthe fly-eye lens 40A has a size not exceeding the size of one cell 42 ofthe fly-eye lens 40B. Herein, the solid-state light-emitting device 11emits light from a light emission region configured of one or moredot-like light-emission spots, or one or more non-dot-likelight-emission spots. The solid-state light-emitting device 11 isconfigured with, for example, one or more light-emitting diodes, one ormore organic EL light-emitting devices, or one or more laser diodes.Therefore, even in a case where the fly-eye lens 40B is disposed on afocal position of the fly-eye lens 40A, each light source image S formedon the fly-eye lens 40B by each cell of the fly-eye lens 40A does nothave a dot-like shape but has a certain size (see FIG. 9). However, inthe embodiment, since one light source image S is not formed over aplurality of cells, light entering the fly-eye lens 40B reaches theillumination area efficiently. Accordingly, light use efficiency in theillumination optical system 1A may be improved.

In addition, in the embodiment, in the case where each cell of thefly-eye lenses 40A and 40B has an aspect ratio other than 1, when thefocal lengths f_(CL1H), f_(CL2H), f_(CL3H), f_(CL1V), f_(CL2V), andf_(CL3V) of the coupling lenses 20A, 20B, and 20C, and the focal lengthsf_(FELH) and f_(FELV) of each of the fly-eye lenses 40A and 40B are setwith the aspect ratio taken into consideration, light use efficiency inthe illumination optical system 1A may be further improved. In addition,in the embodiment, in the case where the coupling lenses 20A, 20B, and20C each have an aspect ratio other than 1, when the focal lengthsf_(CL1H), f_(CL2H), f_(CL3H), f_(CL1V), f_(CL2V), and f_(CL3V) and thenumbers of apertures NA_(1H), NA_(2H), NA_(3H), NA_(1V), NA_(2V), andNA_(3V) of the coupling lenses 20A, 20B, and 20C are set with the aspectratio taken into consideration, light use efficiency in the illuminationoptical system 1A may be further improved. Moreover, in the embodiment,in a case where the traveling-direction angles of the light sources 10A,10B, and 10C are different from one another, when the focal lengthsf_(CL1H), f_(CL2H), f_(CL3H), f_(CL1V), f_(CL2V), and f_(CL3V) and thenumbers of apertures NA_(1H), NA_(2H), NA_(3H), NA_(1V), NA_(2V), andNA_(3V) of the coupling lenses 20A, 20B, and 20C are set with thetraveling-direction angles taken into consideration, light useefficiency in the illumination optical system 1A may be furtherimproved.

Second Embodiment

Configuration

FIGS. 10A and 10B illustrate a schematic configuration of a projector 3according to a second embodiment of the disclosure. Note that theprojector 3 corresponds to a specific example of “a projection typedisplay unit” in the disclosure. FIG. 10A illustrates a configurationexample of the projector 3 viewed from above (from y-axis direction),and FIG. 10B illustrates a configuration example of the projector 3viewed from the side (x-axis direction). FIGS. 11A and 11B illustrate anexample of light paths in the projector 3 of FIGS. 10A and 10B. FIG. 11Aillustrates an example of the light paths of the projector 3 viewed fromabove (y-axis direction), and FIG. 11B illustrates an example of thelight paths of the projector 3 viewed from the side (x-axis direction).

The projector 3 has a configuration different from the projector 1having the illumination optical system 1A in that the projector 3 has anillumination optical system 3A. Accordingly, in the followingdescription, different points from the projector 1 will be mainlydescribed and the description of common points with the projector 1 willbe appropriately omitted.

The illumination optical system 3A includes a coupling lens 20D and adichroic mirror 30C instead of the coupling lenses 20A, 20B, and 20C andthe dichroic mirrors 30A and 30B in the illumination optical system 1A.The dichroic mirror 30C is disposed on a position where optical axes ofthe light sources 10A, 10B, and 10C intersect with one another. Thecoupling lens 20D is disposed on a light exit side of the dichroicmirror 30C and between the dichroic mirror 30C and the integrator 40.

The dichroic mirror 30C includes two mirrors with wavelengthselectivity. Note that the above-described mirrors are each configuredby depositing multilayer interference film. The two mirrors are disposedto be orthogonal to each other so that the surfaces of the mirrors facethe light exit side of the dichroic mirror 30C. As illustrated in FIGS.11A and 11B, for example, the dichroic mirror 30C allows light (lightentering from the light sources 10A and 10B side) entering from a backside of one of the mirrors (hereinafter, referred to as a mirror A forconvenience) to pass therethrough to the front side of the mirror A, andreflects light entering from the front side of the mirror A (lightentering from the light source 10C side) by the mirror A. In addition,as illustrated in FIGS. 11A and 11B, for example, the dichroic mirror30C allows light (light entering from the light sources 10A and 10Cside) entering from a back side of the other mirror (hereinafter,referred to as a mirror B for convenience) to pass therethrough to thefront side of the mirror B, and reflects light entering from the frontside of the mirror B (light entering from the light source 10B side) bythe mirror B. Therefore, the light path unifying device 30 unifiesindividual light fluxes emitted from the light sources 10A, 10B, and 10Cto generate a single light flux.

As illustrated in FIGS. 11A and 11B, for example, the coupling lens 20Dsubstantially parallelizes light entering from the dichroic mirror 30Cside, and converts a traveling-direction angle of the light enteringfrom the dichroic mirror 30C to be equal to or close to atraveling-direction angle of parallelized light.

Functions and Effects

Next, functions and effects of the projector 3 will be described. In theembodiment, as in the first embodiment, the focal length f_(CL4) of thecoupling lens 20D and the focal length f_(FEL) of each of the fly-eyelenses 40A and 40B are set so that each light source image S formed onthe fly-eye lens 40B by each cell of the fly-eye lens 40A has a size notexceeding the size of one cell of the fly-eye lens 40B. Therefore, as inthe first embodiment, light use efficiency in the illumination opticalsystem 3A may be improved.

In addition, in the embodiment, in the case where each cell of thefly-eye lenses 40A and 40B has an aspect ratio other than 1, when thefocal lengths f_(CL4H) and f_(CL4V) of the coupling lens 20D and thefocal lengths f_(FELH) and f_(FELV) of the fly-eye lenses 40A and 40Bare set with the aspect ratio taken into consideration, light useefficiency in the illumination optical system 3A may be furtherimproved. Moreover, in the embodiment, in a case where the coupling lens20D has an aspect ratio other than 1, when the focal lengths f_(CL4H)and f_(CL4V) and the numerical aperture NA_(4H) and NA_(4V) of thecoupling lens 20D are set with the aspect ratio taken intoconsideration, light use efficiency in the illumination optical system3A may be further improved.

Note that the focal lengths f_(CL1), f_(CL2), and f_(CL3) in the firstembodiment are replaced by the focal length f_(CL4) of the coupling lens20D in the second embodiment. Likewise, the focal lengths f_(CL1H),f_(CL2H), and f_(CL3H) in the first embodiment are replaced by the focallength f_(CL4H) in the first direction or a direction correspondingthereto, of the coupling lens 20D in the second embodiment. The focallengths f_(CL1V), f_(CL2V), and f_(CL3V) in the first embodiment arereplaced by the focal length f_(CL4V) in the second direction or adirection corresponding thereto, of the coupling lens 20D in the secondembodiment. The beam sizes φ_(CL1), φ_(CL2), and φ_(CL3) in the firstembodiment are replaced by the beam size φ_(CL4) of light entering thecoupling lens 20D in the second embodiment. The numbers of aperturesNA₁, NA₂, and NA₃ in the first embodiment are replaced by the numericalaperture NA₄ of the coupling lens 20D in the second embodiment. Thesizes h_(CL1), h_(CL2), and h_(CL3) in the first embodiment are replacedby a size h_(CL4) of the coupling lens 20D in the second embodiment. Thebeam sizes φ_(CL1H), φ_(CL2H), and φ_(CL3H) in the first embodiment arereplaced by a beam size φ_(CL4H) in the first direction (for example, inthe lateral direction) or a direction corresponding thereto, of lightentering the coupling lens 20D in the second embodiment. The beam sizesφ_(CL1V), φ_(CL2V), and φ_(CL3V) in the first embodiment are replaced bya beam size φ_(CL4V) in the second direction (for example, in thelongitudinal direction) or a direction corresponding thereto, of thelight entering the coupling lens 20D in the second embodiment. Thenumerical apertures NA_(1H), NA_(2H), and NA_(3H) in the firstembodiment are replaced by the numerical aperture NA_(4H) in the firstdirection or a direction corresponding thereto, of the coupling lens 20Din the second embodiment. The sizes h_(CL1H), h_(CL2H), and h_(CL3H) inthe first embodiment are replaced by a size h_(CL4H) in the firstdirection or a direction corresponding thereto, of the coupling lens 20Din the second embodiment. The sizes h_(CL1V), h_(CL2V), and h_(CL3V) inthe first embodiment are replaced by a size h_(CL4V) in the seconddirection or a direction corresponding thereto, of the coupling lens 20Din the second embodiment. Incidentally, these replacements are similarlyperformed in the subsequent embodiments.

Third Embodiment

Configuration

FIGS. 12A and 12B illustrate a schematic configuration of a projector 4according to a third embodiment of the disclosure. Note that theprojector 4 corresponds to a specific example of “a projection typedisplay unit” in the disclosure. FIG. 12A illustrates a configurationexample of the projector 4 viewed from above (y-axis direction), andFIG. 12B illustrates a configuration example of the projector 4 viewedfrom the side (x-axis direction). FIGS. 13A and 13B illustrate anexample of light paths in the projector 4 of FIGS. 12A and 12B. FIG. 13Aillustrates an example of the light paths of the projector 4 viewed fromabove (y-axis direction), and FIG. 13B illustrates an example of thelight paths of the projector 4 viewed from the side (x-axis direction).

The projector 4 has a configuration different from the configuration ofthe projector 3 having the illumination optical system 3A in that theprojector 4 includes an illumination optical system 4A. Therefore, inthe following description, different points from the projector 3 will bemainly described and the description of common points to the projector 3will be appropriately omitted.

The illumination optical system 4A includes a light source 10D insteadof the light sources 10A, 10B, and 10C, and the dichroic mirror 30C inthe illumination optical system 3A. The light source 10D is arranged onthe optical axis of the coupling lens 20D, and the illumination opticalsystem 4A is configured to allow light emitted from the light source 10Dto enter the coupling lens 20D directly.

The light source 10D has, for example, the solid-state light-emittingdevice 11 and the package 12 which supports and covers the solid-statelight-emitting device 11. The solid-state light-emitting device 11included in the light source 10D emits light from a light emissionregion which is configured of one or more dot-like light-emission spots,or one or more non-dot-like light-emission spots. The solid-statelight-emitting device 11 included in the light source 10D may beconfigured of, for example, a single chip 11A emitting light of apredetermined wavelength range, or a plurality of chips 11A emittinglight of the same wavelength range or different wavelength ranges. In acase where the solid-state light-emitting device 11 included in thelight source 10D is configured of a plurality of chips 11A, the chips11A are arranged, for example, in lateral line, or in lateral andlongitudinal directions, that is, in a lattice.

The chip 11A is configured of a light-emitting diode (LED), an organicEL light-emitting device (OLED), or a laser diode (LD). In the casewhere the light source 10D includes a plurality of chips 11A, all chips11A included in the light source 10D may be configured with one kind ofLEDs, OLEDs, or LDs. In the case where the light source 10D includes aplurality of chips 11A, some chips 11A may be configured with LEDs, andthe other chips 11A may be configured with OLED. Moreover, in the casewhere the light source 10D includes a plurality of chips 11A, some chips11A may be configured with LEDs, and the other chips 11A may beconfigured with LDs. Furthermore, in the case where the light source 10Dincludes a plurality of chips 11A, some chips 11A may be configured withOLEDs, and the other chips 11A may be configured with LDs.

In the case where the light source 10D includes a plurality of chips11A, all chips 11A included in the light source 10D may emit light ofthe same wavelength range or different wavelength ranges. In the casewhere the light source 10D includes a plurality of chips 11A, all chips11A may emit light with wavelength of approximately 400 nm to 500 nm(blue light), may emit light with wavelength of approximately 500 nm to600 nm (green light), or may emit light with wavelength of approximately600 nm to 700 nm (red light). In addition, in the case where the lightsource 10D includes a plurality of chips 11A, the plurality of chips 11Aincluded in the light source 10D may be configured by combination ofchips emitting light with wavelength of approximately 400 nm to 500 nm(blue light), chips emitting light with wavelength of approximately 500nm to 600 nm (green light), and chips emitting light with wavelength ofapproximately 600 nm to 700 nm (red light).

Functions and Effects

Next, functions and effects of the projector 4 in the embodiment will bedescribed. In the embodiment, as in the second embodiment, the focallength f_(CL4) of the coupling lens 20D and the focal length f_(FEL) ofeach of the fly-eye lenses 40A and 40B are set so that each light sourceimage S formed on the fly-eye lens 40B by each cell of the fly-eye lens40A has a size not exceeding the size of one cell of the fly-eye lens40B. Therefore, as in the second embodiment, light use efficiency in theillumination optical system 4A may be improved.

Moreover, in the embodiment, in a case where each cell of the fly-eyelenses 40A and 40B has an aspect ratio other than 1, when the focallengths f_(CL4H) and f_(CL4V) of the coupling lens 20D and the focallengths f_(FELH) and f_(FELV) of the fly-eye lenses 40A and 40B are setwith the aspect ratio taken into consideration, light use efficiency inthe illumination optical system 4A may be further improved. Furthermore,in the embodiment, in a case where the coupling lens 20D has an aspectratio other than 1, when the focal lengths f_(CL4H) and f_(CL4V) and thenumerical aperture NA_(4H) and NA_(4V) of the coupling lens 20D are setwith the aspect ratio taken into consideration, light use efficiency inthe illumination optical system 4A may be further improved.

Fourth Embodiment

Configuration

FIGS. 14A and 14B illustrate a schematic configuration of a projector 5according to a fourth embodiment of the disclosure. Note that theprojector 5 corresponds to a specific example of “a projection typedisplay unit” in the disclosure. FIG. 14A illustrates a configurationexample of the projector 5 viewed from above (y-axis direction), andFIG. 14B illustrates a configuration example of the projector 5 viewedfrom the side (x-axis direction).

The projector 5 has a configuration different from that of the projector4 having the illumination optical system 4A in that the projector 5includes an illumination optical system 5A. Therefore, in the followingdescription, different points from the projector 4 will be mainlydescribed and the description of common points with the projector 4 willbe appropriately omitted.

In the illumination optical system 5A, the optical axes of the lightsource 10D and the coupling lens 20D are tilted to a directionintersecting the optical axis of the integrator 40. The optical axes ofthe light source 10D and the coupling lens 20D are preferably tilted toa lateral direction as illustrated in FIG. 14A. Incidentally, althoughnot illustrated, the optical axes of the light source 10D and thecoupling lens 20D may be tilted to a longitudinal direction or may notbe tilted.

The illumination optical system 5A further includes a polarizationsplitter 80 and a retardation plate array 90. The polarization splitter80 is disposed between the coupling lens 20D and the integrator 40, andthe retardation plate array 90 is disposed between the integrator 40 andthe condenser lens 50 (or the illumination area 60A). In the embodiment,the fly-eye lens 40B is disposed a position which is closer to thefly-eye lens 40A relative to a position of the focal point of thefly-eye lens 40A, and the retardation plate array 90 is disposed on thefocal point (or substantially on the focal point) of the fly-eye lens40A.

The polarization splitter 80 is an optical device with anisotropy topolarization of entering light, and splits (for example, diffracts)light entering from the coupling lens 20D side so that the travelingdirection of S-polarization component is different from that ofP-polarization component. The splitting direction of the polarization ispreferably a lateral direction, however, may be a longitudinaldirection. As illustrated in FIGS. 15A and 15B, for example, thepolarization splitter 80 is preferably a polarization diffraction devicehaving a concave-convex shape on one surface. The concave-convex shapeis configured by arranging in parallel a plurality of strip-shapedconvex sections with blade shape or step shape. Incidentally, thepolarization splitter 80 may be a binary type polarization diffractiondevice, although not illustrated.

The polarization splitter 80 allows light of S-polarization componentcontained in light entering from the coupling lens 20D side to passtherethrough so that an incident angle and an output angle of the lightare equal to (or substantially equal to) each other. Moreover, thepolarization splitter 80 allows light of P-polarization componentcontained in the light entering from the coupling lens 20D side to bediffracted and to pass therethrough so that the incident angle and theoutput angle of the light are different from each other. Note that thepolarization splitter 80 may allow light of P-polarization componentcontained in the light entering from the coupling lens 20D side to passtherethrough so that the incident angle and the output angle of thelight are equal to (or substantially equal to) each other, for example,in contradiction to the above-described example. In this case, thepolarization splitter 80 may further allow light of S-polarizationcomponent contained in the light entering from the coupling lens 20D tobe diffracted and to pass therethrough so that the incident angle andthe output angle of the light are different from each other. It ispreferable that the traveling direction of S-polarized light output fromthe polarization splitter 80 be opposite to and line symmetrical to thetraveling direction of the P-polarized light output from thepolarization splitter 80, in association with relationship with a normal(optical axis) of the polarization splitter 80.

As illustrated in FIG. 16, for example, the retardation plate array 90has first regions 90A and second regions 90B which have different phasedifferences. The first regions 90A are arranged in positions whereeither one of S- and P-polarization components, which are split by thepolarization splitter 80, enters, and the first regions 90A allow lightentering the first regions 90A to pass therethrough with maintaining thepolarization direction. On the other hand, the second regions 90B arearranged in positions where polarization component different from thepolarization component entering the first regions 90A of the S- and theP-polarization components, which are split by the polarization splitter80, enters, and the second regions 90B convert light entering the secondregions 90B into polarized light equivalent to polarized light of lightentering the first regions 90A. The first regions 90A and the secondregions 90B each have a strip shape extending in a direction orthogonalto a splitting (diffraction) direction by the polarization splitter 80,and are arranged alternately in a direction parallel to the splitting(diffraction) direction by the polarization splitter 80. In a case whereeach cell of the fly-eye lenses 40A and 40B has an aspect ratio otherthan 1, both the first regions 90A and the second regions 90B preferablyextend in a direction perpendicular to the longitudinal direction of thefly-eye lenses 40A and 40B.

The total width A_(array) of the first region 90A and the second region90B which are adjacent to each other is, for example, equal to the widthof one cell 42 of the fly-eye lens 40B. In a case where the first region90A and the second region 90B are arranged in a lateral direction, forexample, as illustrated in FIG. 16, the total width A_(array) thereofis, for example, equal to the width (h_(FEL2H)) in the lateral directionof the cell 42. In a case where the first region 90A and the secondregion 90B are arranged in a longitudinal direction although notillustrated, the total width A_(array) is, for example, equal to thewidth (h_(FEL2V)) in the longitudinal direction of the cell 42. Thewidth h_(AWP1) of the first region 90A and the width h_(AWP2) of thesecond region 90B are equal to each other, for example.

Incidentally, in the embodiment, for example, as illustrated in FIGS.17A to 17C, light from the coupling lens 20D side enters thepolarization splitter 80 from an oblique direction. Note that FIG. 17Aschematically illustrates only light paths of S-polarization componentor P-polarization component of the light having entered the polarizationsplitter 80, and FIG. 17B schematically illustrates only light paths ofthe polarization component different from the polarization componentillustrated in FIG. 17A, contained in the light having entered thepolarization splitter 80. FIG. 17C schematically illustrates a statewhere the light paths are shared irrespective of the polarizationcomponent.

For example, light whose optical axis is tilted to a direction (forexample, a lateral direction) parallel to an arrangement direction inthe retardation plate array 90 enters the polarization splitter 80.Therefore, for example, as illustrated in FIGS. 17A and 17B, light ofone of the polarization components contained in the light having enteredthe polarization splitter 80 is emitted in a direction parallel to anoptical axis of incident light, and light of the other polarizationcomponent contained in the light having entered the polarizationsplitter 80 is emitted in a direction intersecting the optical axis ofthe incident light. At this time, a bisector of the optical axis of thelight emitted in the direction parallel to the optical axis of theincident light and the optical axis of the light emitted in thedirection intersecting the optical axis of the incident light ispreferably parallel to (or substantially parallel to) a normal (z-axis)of the polarization splitter 80.

Light emitted in the direction parallel to the optical axis of theincident light is divided into a plurality of fine light fluxes by theintegrator 40 to enter the first regions 90A of the retardation platearray 90, for example, as illustrated in FIG. 17A. In addition, lightemitted in the direction intersecting the optical axis of the incidentlight is divided into a plurality of fine light fluxes by the integrator40 to enter, for example, the second regions 90B of the retardationplate array 90 as illustrated in FIG. 17B, for example. Although notillustrated, the light emitted in the direction parallel to the opticalaxis of the incident light may enter the second regions 90B of theretardation plate array 90 and the light emitted in the directionintersecting the optical axis of the incident light may enter the firstregions 90A of the retardation plate array 90. In either case, one ofthe P-polarization light and S-polarization light is mainly emitted fromthe retardation plate array 90.

The light emitted in the direction parallel to the optical axis of theincident light is divided into fine light fluxes by the fly-eye lens40A, and then each of the divided light fluxes is focused substantiallyin the first regions 90A of the retardation plate array 90 to formsecondary light source planes (light source images S_(A)) at this place(see FIG. 18). Likewise, the light emitted in the direction intersectingthe optical axis of the incident light is divided into fine light fluxesby the fly-eye lens 40A, and then each of the divided light fluxes isfocused substantially in the second regions 90B of the retardation platearray 90 to form secondary light source planes (light source imagesS_(B)) at this place (see FIG. 18). Note that the light source imagesconfigured of the light source images S_(A) and S_(B) correspond to thelight source images S in the above-described embodiment.

In the embodiment, the focal length f_(CL4) of the coupling lens 20D andthe focal length f_(FEL) of each of the fly-eye lenses 40A and 40B areset so that each light source image S₁ and each light source image S₂which is formed on the retardation plate array 90 by each cell 41 of thefly-eye lens 40A has a size not exceeding the size of one cell of thefirst region 90A and one cell of the second region 90B, respectively.

Herein, in a case where both the first region 90A and the second region90B extend in the second direction, the above conditions are expressedby the following expressions (23) and (24). In addition, the aboveconditions are schematically illustrated in FIG. 18.

h _(H1) =P _(4H)*(f _(FEL) /f _(CL4H))≦h _(AWP1)  (23)

h _(H2) =P _(4H)*(f _(FEL) /f _(CL4H))≦h _(AWP2)  (24)

where h_(H1) is a size in the first direction or a directioncorresponding thereto, of the light source image S_(B),

h_(H2) is a size in the first direction or a direction correspondingthereto, of the light source image S_(B),

P_(4H) is a size in the first direction or a direction correspondingthereto, of the light emission region of the solid-state light-emittingdevice 11 included in the light source 10D,

f_(CL4H) is a focal length in the first direction or a directioncorresponding thereto, of the coupling lens 20D,

h_(AWP1) is a size in the arrangement direction of the first region 90A,and

h_(AWP2) is a size in the arrangement direction of the second region90B.

Incidentally, in a case where the solid-state light-emitting device 11is configured of a single chip 11A, P_(4H) is equal to a size in thefirst direction or a direction corresponding thereto, of thelight-emission spot 11B of the chip 11A. In a case where the solid-statelight-emitting device 11 is configured of a plurality of chips 11A,P_(4H) is equal to a size in the first direction or a directioncorresponding thereto, of an enclosure which encloses the light-emissionspots 11B of the all chips 11A with a minimum inner area. Moreover, in acase where the coupling lens 20D is configured of a plurality of lenses,f_(CL4H) is the combined focal length in the first direction or adirection corresponding thereto, of the lenses.

As expressions substantially equivalent to the above-describedexpressions (23) and (24), the following expressions (25) and (26) arecited. The expressions (25) and (26) are especially advantageous in acase where the size of the light emission region of the solid-statelight-emitting device 11 is substantially equal to the size of thesolid-state light-emitting device 11.

h _(H1) =W _(4H)*(f _(FEL) /f _(CL4H))≦h _(AWP1)  (25)

h _(H2) =W _(4H)*(f _(FEL) /f _(CL4H))≦h _(AWP2)  (26)

where W_(4H) is a size in the first direction or a directioncorresponding thereto, of the solid-state light-emitting device 11included in the light source 10D.

Note that in the case where the solid-state light-emitting device 11 isconfigured of a single chip 11A, W_(4H) is equal to the size of the chip11A. In the case where the solid-state light-emitting device 11 isconfigured of a plurality of chips 11A, when all chips 11A are regardedas a single chip, W_(4H) is equal to the size of the single chip.

Functions and Effects

Subsequently, functions and effects of the projector 5 will bedescribed. In the embodiment, the focal length f_(CL4) of the couplinglens 20D and the focal length f_(FEL) of each of the fly-eye lenses 40Aand 40B are set so that each light source image S₁ and each light sourceimage S₂ formed on the retardation plate array 90 by each cell 41 of thefly-eye lens 40A has a size not exceeding the size of one cell of thefirst region 90A and one cell of the second region 90B, respectively.Accordingly, light use efficiency in the illumination optical system 5Amay be improved.

Moreover, in the embodiment, in the case where each cell of the fly-eyelenses 40A and 40B has an aspect ratio other than 1, when the focallengths f_(CL4H) and f_(CL4V) of the coupling lens 20D and the focallengths f_(FELH) and f_(FELV) of each of the fly-eye lenses 40A and 40Bare set with the aspect ratio taken into consideration, light useefficiency in the illumination optical system 5A may be furtherimproved. In addition, in the embodiment, in the case where the couplinglens 20D has an aspect ratio other than 1, when the focal lengthsf_(CL4H) and f_(CL4V) of the coupling lens 20D and the numbers of theapertures NA_(4H) and NA_(4V) are set with the aspect ratio taken intoconsideration, light use efficiency in the illumination optical system5A may be further improved.

Furthermore, in the embodiment, the polarization splitter 80 is disposedin front of the integrator 40, the retardation plate array 90 isdisposed in the rear of the integrator 40, viewed from the light source10D side, and light from the coupling lens 20D is allowed to enter thepolarization splitter 80 in an oblique direction. Therefore, when apolarization plate is used on a light incident side or the like of thespatial modulation device 60, light emitted from the light source 10D isallowed to be converted into polarization light mainly containingpolarization component parallel to a transmission axis of thepolarization plate. As a result, light loss caused in the polarizationplate, which is provided on the light incident side or the like of thespatial modulation device 60, may be decreased, and thus light useefficiency in the entire projector 5 may be substantially improved.

5. Examples

Next, examples of the illumination optical systems 1A, 3A, 4A, and 5Arespectively used in the projectors 1, 3, 4, and 5 according to each ofthe embodiments will be described. FIG. 19 illustrates designed valuesof examples of the first to third embodiments, and FIG. 20 illustratesdesigned value of example of the fourth embodiment. Examples 1 to 3 inthe figure correspond to the designed values common to the illuminationoptical systems 1A, 3A, and 4A, and example 4 in the figure correspondsto the designed values for the illumination optical system 5A.“Conditional Expressions” described at lowermost in FIG. 19 wereobtained by substituting the designed values into the followingexpressions (27) to (29) and (31) to (33). The expressions (27) to (29)and (31) to (33) were obtained by combining the expressions (17) to (22)and expressions in which P_(1H), P_(2H), P_(3H), P_(1V), P_(2V), andP_(3V) in the above-described expressions (7) to (12) were replaced byW_(1H), W_(2H), W_(3H), W_(1V), W_(2V), and W_(3V), respectively.“Conditional Expressions” in FIG. 20 were obtained by substituting thedesigned values into the following expressions (30) and (34) which wereobtained in a similar way. Note that in FIG. 19 and FIG. 20, f_(CL1H),f_(CL2H), f_(CL3H), and f_(CL4H) were collectively described as f_(CLH)for convenience, and f_(CL1V), f_(CL2V), f_(CL3V), and f_(CL4V) werecollectively described as f_(CLV) for convenience. In addition, in FIG.19 and FIG. 20, the numbers of the apertures NA_(1H), NA_(2H), NA_(3H),and NA_(4H) were collectively described as NA_(H) for convenience, andthe numbers of the apertures NA_(1V), NA_(2V), NA_(3V), and NA_(4V) werecollectively described as NA_(V) for convenience.

(w _(1H) /h _(FEL2H))*f _(FELH) ≦f _(CL1H) ≦h _(CL1H)/(2×NA _(1H))  (27)

(w _(2H) /h _(FEL2H))*f _(FELH) ≦f _(CL2H) ≦h _(CL2H)/(2×NA _(2H))  (28)

(w _(3H) /h _(FEL2H))*f _(FELH) ≦f _(CL3H) ≦h _(CL3H)/(2×NA _(3H))  (29)

(w _(4H) /h _(FEL2H))*f _(FELH) ≦f _(CL4H) ≦h _(CL4H)/(2×NA _(4H))  (30)

(w _(1V) /h _(FEL2V))*f _(FELV) ≦f _(CL1V) ≦h _(CL1V)/(2×NA _(1V))  (31)

(w _(2V) /h _(FEL2V))*f _(FELV) ≦f _(CL2V) ≦h _(CL2V)/(2×NA _(2V))  (32)

(w _(3V) /h _(FEL2V))*f _(FELV) ≦f _(CL3V) ≦h _(CL3V)/(2×NA _(3V))  (33)

(w _(4V) /h _(FEL2V))*f _(FELV) ≦f _(CL4V) ≦h _(CL4V)/(2×NA _(4V))  (34)

It is understood from FIG. 19 and FIG. 20 that any designed value may beused to set the focal lengths f_(CL1H), f_(CL2H), f_(CL3H), f_(CL4H),f_(CL1V), f_(CL2V), f_(CL3V), and f_(CL4V) which satisfy the expressions(27) to (34), respectively.

6. Modifications

As described above, although the disclosure has been described withreferring to the several embodiments, the disclosure is not limitedthereto, and various modifications may be made.

Modification 1

For example, in the embodiment, as illustrated in FIGS. 3A and 3B toFIGS. 6A and 6B, the case where the chip 11A is a top emission typeelement has been described, however, the chip 11A may be an end-surfaceemission type element. In this case, as illustrated in FIGS. 21A and 21Bto FIGS. 26A and 26B, for example, the light sources 10A, 10B, 10C, and10D each have a can-type structure in which a solid-state light-emittingdevice 11 configured of one or more end-surface emission type chips 11Ais contained in an inner space enclosed by a stem 13 and a cap 14.

The stem 13 configures, together with the cap 14, a package of the lightsource 10A, 10B, 10C, or 10D, and for example, includes a supportsubstrate 13A supporting a sub mount 15, an outer frame substrate 13Bdisposed on the rear surface of the support substrate 13A, and aplurality of connection terminals 13C. The sub mount 15 is made of amaterial having conductivity and heat radiation property. The supportsubstrate 13A and the outer frame substrate 13B are each configured byforming one or more insulation through-holes and one or more conductivethrough-holes on a substance having conductivity and heat radiationproperty. Each of the support substrate 13A and the outer framesubstrate 13B has, for example, a disc-like shape, and are stacked sothat central axes (not illustrated) of both substrates are coincidentwith each other. The outer frame substrate 13B has a diameter largerthan that of the support substrate 13A. The outer edge of the outerframe substrate 13B is a circular flange projecting toward a radiationdirection from the central axis thereof in a plane whose normal is thecentral axis of the outer frame substrate 13B. The flange has a functionof defining a reference position for fitting the cap 14 in the supportsubstrate 13A in manufacturing process. The plurality of connectionterminals 13C penetrates at least the support substrate 13A. Terminalsexcept for one or more terminals of the connection terminals 13C(hereinafter, referred to as “terminal(s) α” for convenience) areelectrically connected to electrodes (not illustrated) of the individualchips 11A, respectively. For example, the terminals α project longtoward the outer frame substrate 13B side and project short toward thesupport substrate 13A side. Moreover, terminals other than theabove-described terminals α of the connection terminals 13C(hereinafter, referred to as “terminal(s) β” for convenience) areelectrically connected to the other electrodes (not illustrated) of allchips 11A. For example, the terminals β project long toward the outerframe substrate 13B side and the end edges on the support substrate 13Aside of the terminals β are embedded in the support substrate 13A. Ineach connection terminal 13C, a portion projecting long toward the outerframe substrate 13B side corresponds to, for example, a portion embeddedin the substrate or the like. On the other hand, in each connectionterminal 13C, a portion projecting short toward the support substrate13A side corresponds to a portion electrically connected one-to-one tothe chip 11A through a wire 16. In each connection terminal 13C, aportion embedded in the support substrate 13A corresponds to, forexample, a portion electrically connected to all chips 11A through thesupport substrate 13A and the sub mount 15. The terminals α aresupported by the insulation through-holes provided in the supportsubstrate 13A and the outer frame substrate 13B, and the through-holeinsulates and separates the terminals α from the support substrate 13Aand the outer frame substrate 13B. Moreover, the terminals α areinsulated and separated from each other by the above-describedinsulation member. On the other hand, the terminals β are supported bythe conductive through-holes provided in the support substrate 13A andthe outer frame substrate 13B, and are electrically connected to thethrough-holes.

The cap 14 seals the solid-state light-emitting device 11. The cap 14has, for example, a cylindrical portion 14A provided with apertures on atop and a bottom thereof. The bottom of the cylindrical portion 14A is,for example, in contact with a side surface of the support substrate13A, and the solid-state light-emitting device 11 is positioned in aninner space of the cylindrical portion 14A. The cap 14 has a lighttransmission window 14B arranged so as to cover the aperture on the topof the cylindrical portion 14A. The light transmission window 14B isdisposed on a position facing to the light emission surface of thesolid-state light-emitting device 11, and has a function of transmittinglight output from the solid-state light-emitting device 11.

In the modification, the solid-state light-emitting device 11 emitslight from the light emission region configured of one or more dot-likelight-emission spots, or one or more non-dot-like light-emission spots.The solid-state light-emitting device 11 may be configured of, forexample, a single chip 11A emitting light of a predetermined wavelengthrange, a plurality of chips 11A emitting light of the same wavelengthrange, or a plurality of chips 11A emitting light of differentwavelength ranges. In the case where the solid-state light-emittingdevice 11 is configured of a plurality of chips 11A, the chips 11A arearranged in a lateral line as illustrated in FIGS. 21A and 21B and FIGS.22A and 22B, for example, or are arranged in a longitudinal line asillustrated in FIGS. 24A and 24B and 25A and 25B, for example. Thenumber of the chips 11A included in the solid-state light-emittingdevice 11 may be different or the same in the light sources 10A, 10B,10C, and 10D.

In the case where the solid-state light-emitting device 11 is configuredof a single chip 11A, the size (W_(V)*W_(H)) of the solid-statelight-emitting device 11 is equal to the size (W_(V1)*W_(H1)) of thesingle chip 11A as illustrated in FIGS. 23B and 26B, for example. On theother hand, in the case where the solid-state light-emitting device 11is configured of a plurality of chips 11A, when all chips 11A areregarded as one group, the size of the solid-state light-emitting device11 is equal to the size of the group as illustrated in FIGS. 21B, 22B,24B, and 25B, for example. In the case where the plurality of chips 11Aare arranged in a lateral line, the size (W_(V)*W_(H)) of thesolid-state light-emitting device 11 is larger than W_(V1)*3W_(H1) inthe example of FIG. 21B, and is larger than W_(V1)*2W_(H1) in theexample of FIG. 22B. In addition, in the case where the plurality ofchips 11A are arranged in a longitudinal line, the size (W_(V)*W_(H)) ofthe solid-state light-emitting device 11 is larger than 3W_(V1)*W_(H1)in the example of FIG. 24B, and is larger than 2W_(V1)*W_(H1) in theexample of the FIG. 25B.

The chip 11A is configured with, for example, a laser diode (LD). Allchips 11A included in the light sources 10A, 10B, 10C, and 10D may beconfigured with LDs. Moreover, chips 11A included in one or more of thelight sources 10A, 10B, 10C, and 10D may be configured with LDs, andchips 11A included in other light sources may be configured with LEDs orOLEDs.

As illustrated in FIGS. 21A and 21B to FIGS. 26A and 26B, for example,each of the chips 11A includes the light-emission spot 11B having a size(P_(V1)*P_(H1)) smaller than the size (W_(V)*W_(H)) of the chip 11A. Thelight-emission spot 11B corresponds to a region (light emission region)in which light is emitted from the chip 11A when a current is injectedinto the chip 11A to drive the chip 11A. In a case where the chip 11A isconfigured of LD, the light-emission spot 11B is a dot-like shapesmaller than the light-emission spot of the LED or OLED.

In the case where the solid-state light-emitting device 11 is configuredof a single chip 11A, the number of the light-emission spot 11B is oneas illustrated in FIGS. 23B and 26B, for example. On the other hand, inthe case where the solid-state light-emitting device 11 is configured ofa plurality of chips 11A, the number of the light-emission spots 11B isequal to the number of the chips 11A as illustrated in FIGS. 21B, 22B,24B, and 25B, for example. In this case, in the case where thesolid-state light-emitting device 11 is configured of a single chip 11A,the size (P_(V)*P_(H)) of the light emission region as the solid-statelight-emitting device 11 is equal to the size (P_(V1)*P_(H1)) of thelight-emission spot 11B. On the other hand, in the case where thesolid-state light-emitting device 11 is configured of a plurality ofchips 11A, the size (P_(V)*P_(H)) of the light emission region as thesolid-state light-emitting device 11 is equal to the size of anenclosure which encloses the light-emission spots 11B of all chips 11Awith a minimum inner area. In the case where a plurality of chips 11Aare arranged in a lateral line, the size (P_(V)*P_(H)) of the lightemission region is larger than P_(V1)*3P_(H1) but smaller thanW_(V)*W_(H) in the example of the FIG. 21B. Likewise, in the example ofFIG. 22B, the size (P_(V)*P_(H)) of the light emission region is largerthan P_(V1)*2P_(H1) but smaller than W_(V)*W_(H). Moreover, in the casewhere a plurality of chips 11A are arranged in a longitudinal line, thesize (P_(V)*P_(H)) of the light emission region is larger than3P_(V1)*P_(H1) but smaller than W_(V)*W_(H) in the example of FIG. 24B.Likewise, in the example of FIG. 25B, the size (P_(V)*P_(H)) of thelight emission region is larger than 2P_(V1)*P_(H1) but smaller thanW_(V)*W_(H).

Modification 2

Moreover, in the above-described embodiments and the modification,although the illumination optical systems 1A, 3A, 4A, and 5A each areconfigured to include infinite optical system allowing parallelizedlight to enter the fly-eye lens 40A, the illumination optical systems1A, 3A, 4A, and 5A each may be configured to include finite opticalsystem allowing convergent light (or divergent light) to enter thefly-eye lens 40A. In this case, in the above-described embodiments andmodification, in place of the coupling lenses 20A to 20D, atraveling-direction angle conversion device having a function offocusing or dispersing light emitted from the light sources 10A to 10Dmay be disposed. Incidentally, in this case, it is preferable that anoptical magnification of the optical system configured with theabove-described traveling-direction angle conversion device and thefly-eye lenses 40A and 40B be set so that each light source image Sformed on the fly-eye lens 40B by each cell 41 of the fly-eye lens 40Ahas a size not exceeding the size of one cell 42 of the fly-eye lens40B. Specifically, it is preferable that the optical magnification ofthe optical system configured with the above-describedtraveling-direction angle conversion device and the fly-eye lenses 40Aand 40B satisfy the following relational expression.

h=P×m≦h _(FEL2)

where m is an optical magnification of the optical system configuredwith the above-described traveling-direction angle conversion device andthe fly-eye lenses 40A and 40B.

Moreover, in the modification, in a case where each of the cells 41 and42 of the fly-eye lenses 40A and 40B has an aspect ratio other than 1,the illumination optical systems 1A, 3A, 4A, and 5A each are preferablyan anamorphic optical system.

Modification 3

Furthermore, in the above-described embodiments and the modificationsthereof, the case where the present technology is employed to aprojection type display unit has been described, however, the presenttechnology is surely applicable to other display devices. For example,as illustrated in FIG. 27, the present technology is applicable to arear-projection display device 6. The rear-projection display device 6includes the projector 1, 3, 4, or 5 including the illumination opticalsystem 1A, 3A, 4A, or 5A, respectively, and a transmissive screen 7displaying imaging light projected from the projector 1, 3, 4, or 5(projection optical system 70) as illustrated in FIG. 27. In this way,the illumination optical system 1A, 3A, 4A, or 5A is used as theillumination optical system of the rear-projection display system 6 sothat light use efficiency may be improved.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope and without diminishing itsintended advantages. It is therefore intended that such changes andmodifications be covered by the appended claims.

1. An illumination unit comprising: one or more light sources eachincluding a solid-state light-emitting device having a light emissionregion configured of one or more light-emission spots; one or moretraveling-direction angle conversion device each converting atraveling-direction-angle of light entering from the solid-statelight-emitting device; and an integrator including a first fly-eye lenshaving cells which receive light from the traveling-direction angleconversion device and a second fly-eye lens having cells which receivelight from the first fly-eye lens, the integrator uniformalizingillumination distribution in a predetermined illumination area which isto be illuminated by light from the traveling-direction angle conversiondevice, wherein an optical system configured with thetraveling-direction angle conversion device and the first and secondfly-eye lenses has an optical magnification which allows each of lightsource images to have a size not exceeding a size of the cell in thesecond fly-eye lens, the light source images being formed on the secondfly-eye lens by the respective cells in the first fly-eye lens.
 2. Theillumination unit according to claim 1, wherein the solid-statelight-emitting device is configured of a single chip which emits lightin a predetermined wavelength range or is configured of a plurality ofchips which emit light in the same wavelength range or differentwavelength ranges, and the optical magnification of the optical systemsatisfies the following expression:h=P*m≦h _(FEL2) where h is the size of the light source image, P is asize of the light emission region, the size being equal to a size of alight-emission spot of the chip when the solid-state light-emittingdevice is configured of one chip, and the size being equal to a size ofan enclosure which encloses light-emission spots of all the chips with aminimum inner area when the solid-state light-emitting device isconfigured of a plurality of chips, m is the optical magnification ofthe optical system, and h_(FEL2) is the size of the cell in the secondfly-eye lens.
 3. The illumination unit according to claim 2, wherein thetraveling-direction angle conversion device converts atraveling-direction angle of light entering from the solid-statelight-emitting device to be equal to or close to a traveling-directionangle of parallelized light, and a focal length f_(CL) of thetraveling-direction angle conversion device and a focal length f_(FEL)of each of the first and the second fly-eye lenses satisfy the followingexpression:h=P*(f _(FEL) /f _(CL))≦h _(FEL2)
 4. The illumination unit according toclaim 3, wherein each cell of the first and second fly-eye lenses has anaspect ratio other than 1, and the focal length of thetraveling-direction angle conversion device and the focal length of eachof the first and second fly-eye lenses satisfy the followingexpressions:h _(x) =P _(x)*(f _(FELx) /f _(CLx))≦h _(FEL2x)h _(y) =P _(y)*(f _(FELy) /f _(CLy))≦h _(FEL2y) where h_(x) is a size ina first direction of the light source image h_(y) is a size in a seconddirection orthogonal to the first direction, of the light source image,P_(x) is a size in the first direction or a direction correspondingthereto, of the light emission region (when the solid-statelight-emitting device is configured of one chip, the size is equal to asize in the first direction or a direction corresponding thereto, of alight-emission spot of the chip, and when the solid-state light-emittingdevice is configured of a plurality of chips, the size is equal to asize in the first direction or a direction corresponding thereto, of anenclosure which encloses light-emission spots of all chips with aminimum inner area), P_(y) is a size in the second direction or adirection corresponding thereto, of the light emission region (when thesolid-state light-emitting device is configured of one chip, the size isequal to a size in the second direction or a direction correspondingthereto, of a light-emission spot of the chip, and when the solid-statelight-emitting device is configured of a plurality of chips, the size isequal to a size in the second direction or a direction correspondingthereto, of an enclosure which encloses light-emission spots of all thechips with a minimum inner area), f_(FELx) is a focal length in thefirst direction of the first and second fly-eye lenses, f_(FELy) is afocal length in the second direction of the first and second fly-eyelenses, f_(CLx) is a focal length in the first direction or a directioncorresponding thereto, of the traveling-direction angle conversiondevice, f_(CLy) is a focal length in the second direction or a directioncorresponding thereto, of the traveling-direction angle conversiondevice, h_(FEL2x) is a size in the first direction of the cell in thesecond fly-eye lens, and h_(FEL2y) is a size in the second direction ofthe cell in the second fly-eye lens.
 5. The illumination unit accordingto claim 1, wherein the traveling-direction angle conversion device hasa focal length and a numerical aperture which allow light which entersthereto to have a beam size not exceeding a size of thetraveling-direction angle conversion device.
 6. The illumination unitaccording to claim 5, wherein the focal length f_(CL) and the numericalaperture NA of the traveling-direction angle conversion device satisfythe following expression:φ_(CL)=2*f _(CL) *NA≦h _(CL) where φ_(CL) is the beam size of the lightentering the traveling-direction angle conversion device, and h_(CL) isthe size of the traveling-direction angle conversion device.
 7. Theillumination unit according to claim 6, wherein the traveling-directionangle conversion device has an aspect ratio other than 1, and the focallength and the numerical aperture of the traveling-direction angleconversion device satisfy the following expressions:φ_(CLx)=2*f _(CLx) *NA _(x) ≦h _(CLx)φ_(CLy)=2*f _(CLy) *NA _(y) ≦h _(CLy) where φ_(CLx) is a beam size in afirst direction or a direction corresponding thereto, of the lightentering the traveling-direction angle conversion device, φ_(CLy) is abeam size in a second direction or a direction corresponding thereto, ofthe light entering the traveling-direction angle conversion device,NA_(x) is a numerical aperture in the first direction or a directioncorresponding thereto, of the traveling-direction angle conversiondevice, NA_(y) is a numerical aperture in the second direction or adirection corresponding thereto, of the traveling-direction angleconversion device, h_(CLx) is a size in the first direction or adirection corresponding thereto, of the traveling-direction angleconversion device, and h_(CLy) is a size in the second direction or adirection corresponding thereto, of the traveling-direction angleconversion device.
 8. The illumination unit according to claim 1,further comprising a light path unifying device, wherein theillumination unit includes a plurality of light sources and a pluralityof traveling-direction angle conversion devices, each of the lightsources is formed in a manner of a package including the solid-statelight-emitting devices therein, each of the traveling-direction angleconversion devices is arranged for each package, and the light pathunifying device unifies light beams, which have passed through therespective traveling-direction angle conversion devices, into a singlelight path.
 9. The illumination unit according to claim 1, furthercomprising a light path unifying device, wherein the illumination unitincludes a plurality of light sources and one traveling-direction angleconversion device, each of the light sources is formed in a manner of apackage including the solid-state light-emitting device therein, thelight path unifying device unifies light beams emitted from each of thesolid-state light-emitting devices, into a single light path, and thetraveling-direction angle conversion device converts atraveling-direction angle of light emitted from the light path unifyingdevice to be equal to or close to a traveling-direction angle ofparallelized light.
 10. The illumination unit according to claim 1,wherein the illumination unit includes one light source and onetraveling-direction angle conversion device, and the light source isformed in a manner of a package including the solid-state light-emittingdevice therein.
 11. The illumination unit according to claim 2, whereinthe chip is a light-emitting diode, an organic EL light-emitting device,or a laser diode.
 12. The illumination unit according to claim 3,wherein a ratio of a horizontal magnification factor to a verticalmagnification factor of the traveling-direction angle conversion deviceis equal to an inverse of the aspect ratio of each cell in the secondfly-eye lens.
 13. The illumination unit according to claim 1, whereinthe first fly-eye lens is disposed substantially in the focal positionof the second fly-eye lens, and the second fly-eye lens is disposedsubstantially in the focal position of the first fly-eye lens.
 14. Theillumination unit according to claim 1, further comprising: apolarization splitter provided between the traveling-direction angleconversion device and the integrator; and a phase-difference plate arrayprovided between the integrator and the illumination area, wherein thepolarization splitter splitting light, which enters from thetraveling-direction angle conversion device, into S-polarizationcomponent and P-polarization component which travel in directionsdifferent from each other, the phase-difference plate array includesfirst regions and second regions, each of the first regions giving aphase difference different from that of each of the second regions, eachof the first regions is disposed in a position where either one of theS- and P-polarization components split by the polarization splitterenters, and allows light entering the first region to transmittherethrough with maintaining the polarization direction, and each ofthe second regions is disposed in a position where the other of the S-and P-polarization components enters, and converts light, which entersthe second region, into polarized light having the same polarizationdirection of the light which enters the first region.
 15. Theillumination unit according to claim 14, wherein the first regions andthe second regions extend in a direction orthogonal to a splittingdirection of the polarization splitter, and are alternately arranged inthe splitting direction of the polarization splitter, each of the firstregions having a strip shape, and each of the second regions also havinga strip shape.
 16. The illumination unit according to claim 14, whereineach of the cells in the first and second fly-eye lenses has an aspectratio other than 1, and the first regions and the second regions extendin a direction perpendicular to a longitudinal direction of the firstand second fly-eye lenses, each of the first regions having a stripshape, and each of the second regions also having a strip shape.
 17. Theillumination unit according to claim 14, wherein the phase-differenceplate array is disposed substantially on a focal point of the firstfly-eye lens, and the second fly-eye lens is disposed in a positionwhich is closer to the first fly-eye lens relative to a position of thefocal point of the first fly-eye lens.
 18. A projection type displayunit comprising: an illumination optical system; a spatial modulationdevice modulating light from the illumination optical system based on aninput picture signal to generate imaging light; and a projection opticalsystem projecting the imaging light generated by the spatial modulationdevice, wherein the illumination optical system includes one or morelight sources each including a solid-state light-emitting device havinga light emission region configured of one or more light-emission spots,one or more traveling-direction angle conversion device each convertinga traveling-direction-angle of light entering from the solid-statelight-emitting device, and an integrator including a first fly-eye lenshaving cells which receive light from the traveling-direction angleconversion device and a second fly-eye lens having cells which receivelight from the first fly-eye lens, the integrator uniformalizingillumination distribution in a predetermined illumination area which isto be illuminated by light from the traveling-direction angle conversiondevice, wherein an optical system configured with thetraveling-direction angle conversion device and the first and secondfly-eye lenses has an optical magnification which allows each of lightsource images to have a size not exceeding a size of the cell in thesecond fly-eye lens, the light source images being formed on the secondfly-eye lens by the respective cells in the first fly-eye lens.
 19. Adirect view type display unit comprising: an illumination opticalsystem; a spatial modulation device modulating light from theillumination optical system based on an input picture signal to generateimaging light; a projection optical system projecting the imaging lightgenerated by the spatial modulation device; and a transmissive screendisplaying the imaging light projected from the projection opticalsystem, wherein the illumination optical system includes one or morelight sources each including a solid-state light-emitting device havinga light emission region configured of one or more light-emission spots,one or more traveling-direction angle conversion device each convertinga traveling-direction-angle of light entering from the solid-statelight-emitting device, and an integrator including a first fly-eye lenshaving cells which receive light from the traveling-direction angleconversion device and a second fly-eye lens having cells which receivelight from the first fly-eye lens, the integrator uniformalizingillumination distribution in a predetermined illumination area which isto be illuminated by light from the traveling-direction angle conversiondevice, wherein an optical system configured with thetraveling-direction angle conversion device and the first and secondfly-eye lenses has an optical magnification which allows each of lightsource images to have a size not exceeding a size of the cell in thesecond fly-eye lens, the light source images being formed on the secondfly-eye lens by the respective cells in the first fly-eye lens.